Best Way to Do DHW
- Rick 386
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- Location: Royersford, Pa
- Stoker Coal Boiler: AA 260 heating both sides of twin farmhouse
- Hot Air Coal Stoker Stove: LL Hyfire II w/ coaltrol in garage
- Coal Size/Type: Pea in AA 260, Rice in LL Hyfire II
- Other Heating: Gas fired infared at work
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We have kept our AA 260 burning for 6-7 maybe more years in a row now.
Initially we used to just use it for the heating season by starting it around thanksgiving and turning it off near memorial day. Initially my father in law just used the cold oil boiler as the tempering valve. We would always warn everyone when we switched to coal due to the higher temps.
Finally I installed a tempering valve on the coal boiler coil and actually the oil heated water would be hotter.
We have never run out of hot water when on the coal burner. sometimes it may not be as hot and require adjusting the shower control more to the hot side, but all in all, we are happy with just using the coil direct to the hot water lines in the basement. No tank, no buffering, nothing.
Rick
Initially we used to just use it for the heating season by starting it around thanksgiving and turning it off near memorial day. Initially my father in law just used the cold oil boiler as the tempering valve. We would always warn everyone when we switched to coal due to the higher temps.
Finally I installed a tempering valve on the coal boiler coil and actually the oil heated water would be hotter.
We have never run out of hot water when on the coal burner. sometimes it may not be as hot and require adjusting the shower control more to the hot side, but all in all, we are happy with just using the coil direct to the hot water lines in the basement. No tank, no buffering, nothing.
Rick
- Rob R.
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- Location: Chazy, NY
- Stoker Coal Boiler: EFM 520
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You indicated that your DHW load is average, and you are considering an EFM or AA...so I think a tankless coil with tempering valve would work fine for you. When possible, I do like being able to send the heated water from a coil into an electric hot water heater. Modern water heaters are well insulated, offer some buffer capacity, and it is really nice to let the water heater pick up the load when it is time to service the boiler. In the event you forget to turn the boiler back on after service, your other half will still get a warm shower.
-
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Does Rob know this is important because he is a whiz on coal and boiler stuff and a nice guy, or as the result of a harrowing personal experience?Rob R. wrote:In the event you forget to turn the boiler back on after service, your other half will still get a warm shower.
Mike
- Rob R.
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- Stoker Coal Boiler: EFM 520
- Hand Fed Coal Stove: Chubby Jr
2 out of 3.Pacowy wrote:Does Rob know this is important because he is a whiz on coal and boiler stuff and a nice guy, or as the result of a harrowing personal experience?Rob R. wrote:In the event you forget to turn the boiler back on after service, your other half will still get a warm shower.
Mike
- Sting
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- Location: Lower Fox Valley = Wisconsin
- Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG
OK - this is for you pal!SMITTY wrote:I'm hoping Sting will chime in again. That avatar is absolutely WONDERFUL ...
IMO -- Who cares about IMO - I only care about "What you KNOW- not what you "THINK"Pacowy wrote:
Point taken, but IMO overdramaticized.
Mike
There is no possible way to be "over-dramatic or Melodramatic or stupid dramatic" in regard to the damages of DWH scalding
Stop and consider the possibility of skin damage to a young child -- even the "DRAMA" of death before you discount this warning
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- Stoker Coal Boiler: H.B. Smith 350 Mills boiler/EFM 85R stoker
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My point was only that the remedy for this potential problem is known and commonly used; maybe even required by code (?). When you buy a car there is no doubt it could injure or kill people if it doesn't have functioning seatbelts, or if you expose a youngster to airbag deployment. The fact that you may need to use proper and effective safety equipment and procedures doesn't seem like a reasonable basis for ruling out or downgrading the entire option.
Mike
Mike
- dave brode
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- Location: Frostburg, Maryland [western]
- Stoker Coal Boiler: Keystoker KAA-2
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Joe,
Could you locate a normal DHW tank next to the boiler?
I have a normal 50 gallon elec beside my KAA2. A short "gravity" loop runs from the bottom of tank, through the boiler's coil, and back to the top of the tank. I switch the elec off when I have a fire in the boiler. I must note that I also have side-arm style water "pre-heaters" on the boiler piping that warms the well water prior to it entering the tank. I haven't tested to see how much heat they add to the 58* ish water from the well, but some for sure.
Sorry, pics aren't the greatest. Taken during boiler install. The first 3 pics show sloped 'gravity" piping.
Dave
Could you locate a normal DHW tank next to the boiler?
I have a normal 50 gallon elec beside my KAA2. A short "gravity" loop runs from the bottom of tank, through the boiler's coil, and back to the top of the tank. I switch the elec off when I have a fire in the boiler. I must note that I also have side-arm style water "pre-heaters" on the boiler piping that warms the well water prior to it entering the tank. I haven't tested to see how much heat they add to the 58* ish water from the well, but some for sure.
Sorry, pics aren't the greatest. Taken during boiler install. The first 3 pics show sloped 'gravity" piping.
Dave
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Last edited by dave brode on Tue. Nov. 19, 2013 10:12 pm, edited 2 times in total.
- dave brode
- Member
- Posts: 478
- Joined: Fri. Jan. 15, 2010 5:47 pm
- Location: Frostburg, Maryland [western]
- Stoker Coal Boiler: Keystoker KAA-2
- Hand Fed Coal Boiler: used to have a 5 section Red Square
- Coal Size/Type: rice anthracite
Pic showing the "side arm" style pre-heaters on boiler piping. Well water pics up heat from return then supply, then down to tank inlet. Other "in pipe" is for summer use, bypasses side-arms. The "side arms" are valved off, so water doesn't travel through them in summer.
note: side arm style heat exchangers are made by running 1.5" boiler piping through 2" [ground stops out of the tees]
note - there is one big difference between what's shown and how piping is run now. Supply water from side arms to DHW tank now does not run into normal top inlet of the tank. It now runs down and tees into the gravity loop at the bottom of tank. Water can enter both the bottom of the tank, AND the boiler's coil from said tee. This forces at least some of the supply water through the boiler's coil while water is being drawn. How much, I'm not sure, but it made a huge improvement. Hot water is pretty much endless now. Prior to the change, a 2nd consecutive shower was getting cool.
I can post pics of the change if you are interested.
Dave
note: side arm style heat exchangers are made by running 1.5" boiler piping through 2" [ground stops out of the tees]
note - there is one big difference between what's shown and how piping is run now. Supply water from side arms to DHW tank now does not run into normal top inlet of the tank. It now runs down and tees into the gravity loop at the bottom of tank. Water can enter both the bottom of the tank, AND the boiler's coil from said tee. This forces at least some of the supply water through the boiler's coil while water is being drawn. How much, I'm not sure, but it made a huge improvement. Hot water is pretty much endless now. Prior to the change, a 2nd consecutive shower was getting cool.
I can post pics of the change if you are interested.
Dave
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- Lightning
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Option 2 hands down.. Why fiddle with coal in the summer for two people? For a family of 6, yeah sure... Doesn't seem to me it would warrant the heating load for two people.. Do a good job prepping it in the spring and forget about it till fall.. Plumb in a bypass so cold water isn't going thru it.NJJoe wrote:Option 2. Use the boiler DHW coil and plumb the output to the input of a water heater. The coil could preheat the water entering the water heater and possibly lead to less water heater energy usage.
Expected DHW usage is for 2 people at the moment doing regular laundry loads, showers/baths, dishwashing and cleaning. Would like to build reserve capacity into this system for possibly more people.
Nothing is built, this is still in planning phase. Any opinions would be appreciated. Thanks...
Amen Brother!! Save summer for summer stufftitleist1 wrote: one reason I like the change of seasons because I get tired of doing the same chores. I get tired of cutting grass toward the end of summer while at the same time I look forward to starting up the coal stove, I get tired of raking leaves and am glad when they are all back in the woods, but look forward to moving the occasional snow we get, by the time spring rolls around I am ready to shut down the coal stove (blasphemy, I know) and not have to deal with loading it up and emptying the ash, but I look forward to cutting grass.
i said all that to justify my personal choice - option 2! (with the bypass you mentioned)
- dave brode
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- Posts: 478
- Joined: Fri. Jan. 15, 2010 5:47 pm
- Location: Frostburg, Maryland [western]
- Stoker Coal Boiler: Keystoker KAA-2
- Hand Fed Coal Boiler: used to have a 5 section Red Square
- Coal Size/Type: rice anthracite
Joe,NJJoe wrote:Yes please. Perhaps a before and after pic would help me to understand what you accomplished here and how it is supposed to work.dave brode wrote:I can post pics of the change if you are interested.
Will do. send me a pm if I forget and don't post back by the weekend
- dave brode
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- Posts: 478
- Joined: Fri. Jan. 15, 2010 5:47 pm
- Location: Frostburg, Maryland [western]
- Stoker Coal Boiler: Keystoker KAA-2
- Hand Fed Coal Boiler: used to have a 5 section Red Square
- Coal Size/Type: rice anthracite
Joe,
I'll post pics. Realize that what I'm calling 'side-arm" style heat exchangers on my boiler mains are functioning as pre-heaters. They heat the water coming from the well. The syphon, or gravity loop connected to my boiler's coil is doing most of the work.
The water comes from the well, and goes through the sidearm on the boiler's return, then jumps over to the sidearm on the boiler's supply. The water from well then goes down to the tee at the bottom, of the tank. From there it goes into the bottom of the tank, AND through the coil, and back to inlet in the side of the tank. Prior to the change, the water from the well ran only into the normal top inlet of the elec tank, and the gravity loop heated the water parked in the tank. That piping routing is shown in the Nov 19th post. Prior to that change, when water was drawn, it went directly into the normal top inlet in the tank. Now, the water enters the tank through either [both side inlets on the tank. None enters the normal top inlet.
Dave
I'll post pics. Realize that what I'm calling 'side-arm" style heat exchangers on my boiler mains are functioning as pre-heaters. They heat the water coming from the well. The syphon, or gravity loop connected to my boiler's coil is doing most of the work.
The water comes from the well, and goes through the sidearm on the boiler's return, then jumps over to the sidearm on the boiler's supply. The water from well then goes down to the tee at the bottom, of the tank. From there it goes into the bottom of the tank, AND through the coil, and back to inlet in the side of the tank. Prior to the change, the water from the well ran only into the normal top inlet of the elec tank, and the gravity loop heated the water parked in the tank. That piping routing is shown in the Nov 19th post. Prior to that change, when water was drawn, it went directly into the normal top inlet in the tank. Now, the water enters the tank through either [both side inlets on the tank. None enters the normal top inlet.
Dave
- dave brode
- Member
- Posts: 478
- Joined: Fri. Jan. 15, 2010 5:47 pm
- Location: Frostburg, Maryland [western]
- Stoker Coal Boiler: Keystoker KAA-2
- Hand Fed Coal Boiler: used to have a 5 section Red Square
- Coal Size/Type: rice anthracite
I'll post some pics asap. I have a new computer, and a new camera. I'm having a helluva time with both
- dave brode
- Member
- Posts: 478
- Joined: Fri. Jan. 15, 2010 5:47 pm
- Location: Frostburg, Maryland [western]
- Stoker Coal Boiler: Keystoker KAA-2
- Hand Fed Coal Boiler: used to have a 5 section Red Square
- Coal Size/Type: rice anthracite
1st pic shows the original route from side arms down to normal inlet in top of tank. the two valves on the piping above the tank allowed bringing water directly from well, or routing through side arms.
2nd pic shows original connection of bottom of gravity loop from bottom of tank through boiler's coil, and back into side inlet high in tank.
3rd shows gravity loop top connection to tank.
4TH is a not too good pic that barely shows the loop's connections at boiler's coil.
This is how I originally had it piped. The loop did keep parked water hot, but a 2nd shower, or a shower after a load of laundry was getting cold. Even so, I still switched elect tank off when there was a fire in the boiler. After the water in the tank cooled some, it would take a few hours for the gravity loop to bring it back up. Fwiw, I did have a small pump on the gravity loop for a while. it could be used to speed up the gravity loop, but for reasons that I will not go into right now, I scrapped that some time ago.
2nd pic shows original connection of bottom of gravity loop from bottom of tank through boiler's coil, and back into side inlet high in tank.
3rd shows gravity loop top connection to tank.
4TH is a not too good pic that barely shows the loop's connections at boiler's coil.
This is how I originally had it piped. The loop did keep parked water hot, but a 2nd shower, or a shower after a load of laundry was getting cold. Even so, I still switched elect tank off when there was a fire in the boiler. After the water in the tank cooled some, it would take a few hours for the gravity loop to bring it back up. Fwiw, I did have a small pump on the gravity loop for a while. it could be used to speed up the gravity loop, but for reasons that I will not go into right now, I scrapped that some time ago.